1. FIELD OF INVENTION
My invention generally relates to beneficiation of particulate ores in a fluidic medium and more particularly to apparatus that uses both fluid flow and gravity, aided by a particular multi-port valving system, to accomplish its purpose.
2. DESCRIPTION OF PRIOR ART
The difference in density between heavier ore material and lighter gangue material has long been used as a basis of separating a mixture of the two materials to recover the metallifeours ore fraction. This is especially true in particulate mixtures of the heavier metals, such as in the case of deposits of alluvial gold, platinum group metals, and the like in sands. Commonly, such beneficiation processes have been accomplished in a fluidic medium such as water, with the aid of gravity, by moving the particulate material in the fluidic media so that it might be acted upon by gravity while in suspension to cause the particulate materials to tend to separate with the more dense material nearest the gravity source.
This type of device has been used especially to separate or beneficiate alluvial deposits of gold and black sands from parent gangue material. Devices for accomplishing this separation have generally involved moving the particulate material relative to a fluid bed, commonly water. Such devices have accomplished this relative motion of fluid and particles in a substantially horizontally oriented course, as in the case of an ordinary sluice box, or in a substantially vertically oriented fashion, as in the case of jigs or fluidic bed separators. Many and various devices of each type have heretofore become known. My invention provides a separator of this general type that embodies the better features of both the sluice-type and a fluidic bed type separators, while yet minimizing the poorer features of each process.
My invention provides an initially vertically oriented fluid flow that changes its course to a substantially horizontal flow prior to exhaustion. This is accomplished by a fluid container with a lower fluid input chamber divided from an upper processing chamber by medial structure including a valving plate having a plurality of valved orifices to allow fluid flow from the lower chamber to the upper chamber over a substantial area. An exhaust orifice is provided in the medial portion of the medial structure so that fluid will move vertically upwardly through the valving structure and then subsequently horizontally to the exhaust system. Prior art devices have generally provided either vertical or substantially horizontal motion of fluid and suspended particulate material being beneficiated, but generally have not provided any appreciable amount of both types of fluid flow in the same device.
My invention further carries a plate of some areal extent to support ore to be beneficiated at a spaced distance above the medial structure dividing the lower chamber from the upper chamber, so that the ore will be contacted by water in the upper chamber and moved downwardly over the periphery of its support plate to enter the treatment area in the medial portion of the device by the water. This causes the ore to enter the treatment area about the periphery of that area so that the ore during treatment will be moved inwardly to the exhaust area. During this course of transit, however, the particulate ore will also be acted upon by the vertically upwardly directed flow of water passing from the lower water chamber to the upper treatment chamber. Prior art devices have generally provided either the horizontal or vertical motion of ore material, but have not in general combined such motion, as does the instant device.
Entrapment means for heavier, more dense particles, including a plate of substantial areal extent defining a plurality of holes and a screen element therebeneath, are carried immediately above the valving plate between the water chamber and the treatment chamber. Water entering the treatment chamber passes vertically upwardly from the valving plate through the entire medial structure so that as particulate material moves thereover, its heavier particles move vertically downwardly into and through the orifices in the screen and hole defining plate to create an action similar to that of the traditional sluice. At the same time, the particles are acted upon by the water moving vertically through the entrapment structure to create somewhat of a fluidic bed-type action that tends to act upon particulate matter in the entrapment structure to further refine its separation by moving lighter particles upwardly and heavier particles downwardly. This latter fluidic bed-type action is particularly useful in recovering smaller particles of gold, such as that commonly referred to as flour gold and having a major dimension in the few micron range and a generally flat, plate-like shape. Such particles tend to be difficult to segregate in any beneficiator and are almost impossible to segregate in a sluice-type device, but my invention is quite adaptable to segregating such particles because of its combined type of action, its particular valving system and the functions resulting therefrom. By reason of this action, flour gold may not only be entrapped in the screen and hole structure but also in the valving structure itself or even in the fluid entry chamber therebelow.
My invention also provides secondary features distinguishing it from the prior art. It uses a relatively small amount of water in proportion to the amount of ore being processed and that water may be recycled, if desired, to allow the device to be used in areas where water is not readily available and must be conserved. The operation of my apparatus is also substantially automatic so that it may be readily and rapidly learned by a person who is substantially unsophisticated in the ore beneficiating art. In massive hydraulic mining operations where large volumes of material varying substantially in size must be dealt with, my invention is particularly useful as a secondary beneficiator to concentrate more dense ore materials from the output of traditional sluice apparatus that has already performed a primary beneficiation function.
My invention also allows quite a wide variation of parameters relating to the ore beneficiation to adapt if for efficient use with particular types of ore. The fluid used in the device may be different than water to vary the density of the fluid bed. The amount of fluid flow may be readily regulated by fluid input volume or pressure, by change in valving orifice size and ball valve weights, and by change of entry orifice size and array. The entrapment structure may be varied by changing the size and array of orifices therein to accomodate particular materials. The input of particulate ore into the device may be varied by changing the size or shape of the ore supporting plate and its vertical position relative to the entrapment structure, all of which will also effect the entrapment process itself. Though a cylindrical configuration of the device is illustrated and preferred, this configuration may also be changed to accommodate particular situations.
My invention differs from the prior art, not in any one of these features or structures, per se, but rather in the synergistic combination of all of them to provide the functions necessarily flowing therefrom, as hereinafter set forth and claimed.